A. Technical Field
This invention relates generally to optical transport networks, and more particularly to the maintenance of correlated virtual data streams within a network.
B. Technical Field
High-speed, long-haul transport networks are able to communicate large amounts of information across significantly large distances. These networks transmit this information within the optical domain by modulating one or more optical signals. These optical signals may have different wavelengths and can be multiplexed together into a wave-division multiplexed optical signal, which is transported between a long-haul transmitter and receiver using optical fiber.
FIG. 1 illustrates an exemplary transport connection 100 between a long-haul transmitter 110 and receiver 120 that carries multiple channels or signals at different wavelengths (e.g., 130, 135) for optically communicating information from the transmitter 110 to the receiver 120. Connection 100 may include one or more optical fibers.
A transport network is oftentimes unable to efficiently use the available bandwidth within one or more of the channels in the transport system. For example, first channel 130 may be carrying client data at a rate (e.g., 2.5 Gbps) that is significantly slower than the capacity of channel 130 (e.g., 10 Gbps) which results in an under-utilization of the channel bandwidth and wasted capacity. Such wasted capacity not only reduces the efficiency of the transport network but also introduces additional cost to the customer and/or network provider.
In another example, the first channel 130 and a second channel 135 may collectively carry client data at a rate that exceeds the capacity of either channel individually. Such transmission on two wavelengths may also introduce inefficiencies depending on the rates of the client data and transport channels. For example, the first 130 and second 135 channels may each have a capacity of 10 Gbps, but collectively transmit client data at 15 Gbps, thereby resulting in wasted bandwidth in either one or both of the channels.
The cost of inefficient bandwidth use within a transport system is absorbed by either a customer, who must pay for the unused capacity, or a service provider who is unable to monetize the unused capacity. Additionally, this relationship between a client data rates and transport channel capacity is often static, such that bandwidth allocation is difficult to change with changing network conditions.